I know there are many posts out there about the differences between these two patterns, but there are a few things that I cannot find.
From what I have been reading,
A lot of the previous answers do not provide code comparisons between Abstract Factory and Factory Method pattern. The following is my attempt at explaining it via Java. I hope it helps someone in need of a simple explanation.
As GoF aptly says: Abstract Factory provides an interface for creating families of related or dependent objects without specifying their concrete classes.
public class Client {
public static void main(String[] args) {
ZooFactory zooFactory = new HerbivoreZooFactory();
Animal animal1 = zooFactory.animal1();
Animal animal2 = zooFactory.animal2();
animal1.sound();
animal2.sound();
System.out.println();
AnimalFactory animalFactory = new CowAnimalFactory();
Animal animal = animalFactory.createAnimal();
animal.sound();
}
}
public interface Animal {
public void sound();
}
public class Cow implements Animal {
@Override
public void sound() {
System.out.println("Cow moos");
}
}
public class Deer implements Animal {
@Override
public void sound() {
System.out.println("Deer grunts");
}
}
public class Hyena implements Animal {
@Override
public void sound() {
System.out.println("Hyena.java");
}
}
public class Lion implements Animal {
@Override
public void sound() {
System.out.println("Lion roars");
}
}
public interface ZooFactory {
Animal animal1();
Animal animal2();
}
public class CarnivoreZooFactory implements ZooFactory {
@Override
public Animal animal1() {
return new Lion();
}
@Override
public Animal animal2() {
return new Hyena();
}
}
public class HerbivoreZooFactory implements ZooFactory {
@Override
public Animal animal1() {
return new Cow();
}
@Override
public Animal animal2() {
return new Deer();
}
}
public interface AnimalFactory {
public Animal createAnimal();
}
public class CowAnimalFactory implements AnimalFactory {
@Override
public Animal createAnimal() {
return new Cow();
}
}
public class DeerAnimalFactory implements AnimalFactory {
@Override
public Animal createAnimal() {
return new Deer();
}
}
public class HyenaAnimalFactory implements AnimalFactory {
@Override
public Animal createAnimal() {
return new Hyena();
}
}
public class LionAnimalFactory implements AnimalFactory {
@Override
public Animal createAnimal() {
return new Lion();
}
}